The mass extinction at the end of the mesozoic era was caused by a.. solar radiation. c.. an ice age. b.. a meteor or asteroid colliding with earth. d.. volcanic activity.

B. A meteor or asteroid colliding with the Earth.

The Mesozoic Era lasted for approximately 180 million years and ended at about 250 to 65 million years ago. The 'Great Extinction' happened in this era and it marked an end to almost all forms of life.

Will you become my friend.